1. Field of the Invention
The present invention deals with the field of syringe devices usable with hypodermic needle constructions. It is often convenient to construct such devices such that the portion of the hypodermic needle which penetrates the skin of the patient is disposable whereas the remainder of the syringe body is reusable. Basically, a hypodermic syringe is usable for the injection of fluids at selective locations within the soft tissues of the human body. However, it is often desirable to withdraw fluids, most usually blood or urine from the human body for various reasons.
When fluids are withdrawn by persons by the use of a hypodermic syringe, it is desirable to prevent any secondary contamination of the fluids, so withdrawn, subsequent to entering syringe body. In this respect, it is desirable to provide a means for minimizing contact between the atmosphere or any other contaminating agent and a fluid which has recently been withdrawn. In hospitals to seal a syringe, laboratory technicians, nurses and physicians often resort to bending the needle at the end of a syringe to minimize contact between the atmosphere and the withdrawn fluid. Such a procedure is initially dangerous to the technician or nurse and also does not provide an effective hermetic seal. Another attempt to maintain the withdrawn fluid in a sterile condition is to insert the needle immediately into a cork or similar device. These primitive methods have been utilized to prevent secondary contamination of withdrawn blood and the like since previously designed constructions for providing a sterile syringe have been either too costly or proved to be inefficient in operation. It would be desirable to have an effective device such as shown under the present invention which would enable the fluid within the hypodermic syringe to be sealed while the hypodermic needle is still located within the body of the patient. In this manner, secondary contamination of the reservoir within the housing of the syringe device is minimized.
2. Description of the Prior Art
Many patents have been granted on syringe devices which are usable with hypodermic needles for sealing the internal environment of the syringe device with respect to the external ambient atmosphere. One such U.S. Pat. is No. 3,872,864 issued Mar. 25, 1975 to Allen in which a plurality of internal sealible chambers is provided for use with a double syringe assembly for prefilled plastic syringes which are completely disposable. This design and those similar thereto include complicated sealing arrangements and isolating devices. Most of these designs are usable for maintaining a fluid within the syringe in an uncontaminated condition prior to insertion in the soft tissue of the human body. The present invention has a primary useful function in the field of syringes used for the withdrawing of fluids from the human body.
When fluids are withdrawn from the human body, the main problem is to place the withdrawn fluid within a culture medium for isolation of bacterial or viral contaminants. The difficulty arises when secondary contamination occurs during the transference from the syringe device to the location of the culture medium. During this critical time period, a secondary contamination could occur which would erroneously suggest the presence of a bacterial or viral entity within the blood of the subject which has entered the culture medium only by way of the secondary contamination and not as a result of being located within the body of the subject. The present invention includes a design for eliminating such secondary contaminations.